Protractor



J y 1951 w. B. WEYRICK 2,562,224

- PROTRACTOR Filed March 29, 1945 Imlllllllil INVENTOR. We: r? 5. W22Heir I? fforng,

H from the right of Figure 1.

Patented July 31, 1951 UNITED STATES PATENT OFFICE PROTRACTOR Warren B.Weyrick, Akron, Ohio Application March 29, 1945, Serial No. 585,534

' 4 Claims. (01. 3375) This invention relates to protractors. An objectof the invention is to provide an improved protractor of simple compactconstruction and by which readings of angles may be readily made withoptimum accuracy.

Anotherobject of the invention is to provide and the-accompanyingdrawings.

.Of the accompanying drawings: Figure 1 is a front elevational view of aprotractor embodying the invention.

Figure 2 is a side elevation thereof as viewed Figure 3 is a viewsimilar to Figure 1, but

illustrating the protractor in another position of use for measuring anangle.

Figure 4 is a view similar to Figure 1 illustratinga modified vform ofthe invention.

Figure 5 is an enlarged cross-section taken substantially on line 5-5 ofFigure 4.

Figure 6 is a view similar to Figure 1 illustrate ing another modifiedform of the invention.

Figure 7 is a fragmentary view of the device one end of plate Ill andequidistant from side edges H and I2 thereof.

Plate I4 is provided, outwardly of pivot I3,

' with a straight-edged portion l5 which forms an outside angle with oneside ed e H and which .may be of length substantially equal to the Widthof plate H], as shown. The lateral end of plate I4 adjacent said sideedge ll may be rounded as shown so as not to project beyond a radiusfrom pivot l3 equal to the distance from the pivot to the side edge.Plate [4 may have the other lateral end thereof extended to provide astraighted'ged portion l6 which projects outwardly of straight side edge12 a substantial distance, this straight edge [6 being in parallelismwith edge 15 and forming an inside angle with said side edge l'2. Theedges H and I2 of plate In and edges l5 and IBof member M, respectively,being in parallelism it will be seen that all angles which edge portionsl2 and I6 make with each other, as member I4 is pivoted relatively ofplate III, will be equal to corresponding angles formed between edgeportions II and 15. The pivot end of plate I0 is cut back at angles froma radius about pivot 13, as indicated at lob and I00, so that the platewill not project beyond straight-edged portion 15 in any angularposition of adjustment of plate 10 and member l4. The edge portions [5and I6 of plate 14 preferably are substantially close to pivot 13 forcompactness and simplicity of design.

The member 14 may be shaped to provide a narrow indicator or finger 20which extends longitudinally of plate Ill to adjacent the end thereofopposite to pivot l3, the free end of this indicator having a mark 2! orother means thereon for indicating, on a scale 22 marked on plate In,the various angles between adjacent straight edged portions, aspreviously described. The indicator, as shown in Figure 1, is set toread zero when the straight edged portions are at right angles to eachother, and-the scale is marked to indicate angles within a range ofninety degrees plus or minus fifteen degrees, this range beingsatisfactory for a maximum of practical uses of the device, as bymechanics, engineers, draftsmen, inspectors, checkers and many otherskilled craftsmen; Itwill be seen however, that the range of readingsmay be increased, but possibly at the expense of increasing theproportions of the device. To obtain maximum range of degrees on thescale 22 the zero mark is equidistant from side edges II and I2 of plateI0, that is, it is on the longitudinal center line of said plate. Anaperture 23 or other suitable non-skid means is provided adjacent thefree end of the indicator to facilitate swinging member 14 relatively ofplate I0, about pivot l3.

For releasably locking member 14 to plate ID in any position of angularadjustment thereof there may be provided on indicator 2|], intermediatethe free end thereof and pivot I3, a slotted enlargedportion 25 througha curved slot 25 of which extends a threaded pin 26 which is secured toplate I0, the pin 26 having a nut 21 threaded thereon for clamping saidmember and plate together. The slot 25 is curved on a radius from pivotl3.

In the use of the invention described above as for checking the outsideangle of a strip of ninety-degree angle-material, the nut 21 is loosenedandthe device is applied to the material, as indicated in chain-dottedlines in Figure 1, after which the nut may be tightened to clamp plateand member 14 together, the angle being directly readable on scale 22.Conversely, the angle may be first set on the scale and the partsclamped together so that an angle strip or other part may be worked orformed to a desired angle. Likewise the same settings may be utilizedfor checking or transposing an inside angle. Figure 3 illustrates thedevice as set for reading an inside angle of greater than ninety degrees(seechain-dotted lines), or an outside angle of the same number ofdegrees.

In Figures 4 and 5 is shown a protractor substantially like that shownin Figures 1 to 3, except that member Ma, corresponding to member 14, ismade in two parts, the part IBa for-the projecting straight-edgedportion being pivoted to member Ma at Mb. A detent 30 is provided onpart lGa, in spaced relation topivot Mb, for releasable engagement ineither one or other of two depressions 3i and 32 in member I 4a, toretain said part either in an operative position thereof shown inchain-dotted lines in Figure 4 or in a retracted inoperative position,as shown in Figures 4- and 5. The operation of this modified form of theinvention is otherwise the same as previously de-- scribed, like partsbeing given'like numerals with a sufiix a except as otherwise noted.Referring to Figure 6 there is illustrated another modified form of theinvention, designed particularly for measuring inside angles. A plate 40is of trapezoid shape providing one straight lateral side edge 4|, thewidth and shape of the plate otherwise being as desired to measurewithin a desired range of degrees, as will be described. Pivoted at 42at one corner of plate 46, closely adjacent edge 4|, may be aquadrantshaped plate or member 43, one straight edge 44 of which formsan outside angle with said edge 4|. A narrow indicator or finger extendsfrom plate 43, angularly of' edge 4!, to' adjacent the other end ofplate 40 and is provided with a mark The scale shown is designed to Forclamping the device v42, said pin having a nut 4"! threaded thereon andoperable as previously described.

In Figure '7 is shown a protractor which is similar in all respects tothat illustrated in Figures 1 and 2, except that plate I4 is rounded atI40 and Md on a radius from pivot 13 equal to half the width of plate[4, so that bearing surface will be assured beyond the pivot ends ofside edges I I and I2 and in alignment therewith.

Thus has been provided a novel protractor which accomplishes the statedobjects of the invention. Other modifications thereof may be resorted towithout. departing from the spirit of l the invention or the scope ofthe appended claims.

What is claimed is: l. A protractor comprising a plate providingopposite straight lateral side edges in parallelism,

a member superposed on said plate and being pivoted thereto at a pointsubstantially closely adjacent one end of the plate, said member havingan outer straight edge portion longitudinally outwardly of said pivot tolie free and unob- ,structed' beyond the pivot end of said plate andlaterally across the same within a predetermined range'o'fvarious-angularly adjusted positions of l, saidmember on said pivot withrespect to said plate;"sa'id outer straight edge portion of said 4member extending in lateral direction from said pivot toward one of saidstraight lateral side edges of said plate but not beyond said side edgein any said angularly adjusted position of said plate and member andthereby defining a variable outside angle corner on the protractor forgauging inside angle corners, said member having an inner straight edgeportion parallel to said outer straight edge portion thereof projectingbeyond the other said straight lateral *side edge of said plate andthereby forming therewith an inside angle corner which is variablecorrespondingly to the angles of said outside angle corner of theprotractor for gauging outside angle corners, and

'means-on said plate and member for indicating the angular variations ofsaid inside and outside angle corners of the protractor, said pivotbeing equidistant from said lateral side edges of said plate, the edgeportions at said one end of said plate being inwardly divergent from apoint at a. radius from said pivot.

2. A protractor comprising a plate providing opposite straightlateral'side edges in parallelism, a member superposed on said plate andbeing pivoted thereto at a point substantially closely adjacent one endof the plate, said member having an outer straight'edge portionlongitudinally outwardly of said pivot to 'lie free and unobstructedbeyond the pivot end of said late and laterally across the same within-apredetermined range of angularly adjusted positions of I said member onsaid pivot with respect to said plate, said outer straight edgeportionof said member extending in lateral direction from said pivottoward one of said straight lateral side edgesof said plate but notbeyond said side edge in'any said angularly adjusted position ofsaid-plate and member and thereby defining a variable outside anglecorner on the protractor for gauging inside angle corners, said memberhaving an inner straight edge portion parallel to said outer straightedge portion'thereof' projecting beyond the other said straight lateralside edge'of said plate and thereby forming therewith an inside anglecorner which is variable correspondingly to the anglesof said outsideangle corner of the protractorfor gauging outside angle corners andmeans on said plate and member for indicating the angular variations ofsaid inside and outside angle corners of'the protractor, .theedgeJportions of said one end of saidplatebeing inwardly divergent froma point at a radius fromsaid pivot, said pivot being equidistantfromsaid .lateral side edges of said plate, said memberihaving arcuateportions on a radius from said pivot equal to half the distance betweensaid side edges.

3. A protractor comprising a plate providing opposite straight lateralside edges inparallelism, a member superposed on said plate and beingpivoted thereto at a point substantially' closely adjacent oneend of theplate, .said member having an outer straight edge portion longitudinallyoutwardly of said pivot to lie free and unobstructed beyond the pivotend of said.- plate and laterally across the same within a predeterminedrange of various angularly adjusted'positions ofsaid member on saidpivot'with respect to said plate, said outer straight edge portion ofsaid member extending in. lateral: direction from said pivot toward oneof said straight lateral side edges of said plate but not beyond saidside edge in any angularly; adjusted position of said plate and memberand therebydefining a variable outside angle-comer OII tBQ'PID- tractor'forgauging inside: an le com rsg fiq member having an inner straightedge portion parallel to said outer straight edge portion thereofprojecting beyond the other said straight lateral side edge of saidplate and thereby forming therewith an inside angle corner which isvariable correspondingly to the angles of said outside angle corner ofthe protractor for gauging outside angle corners, and means on saidplate and member for indicating the angular variations of said insideand outside angle corners of the protractor, said inner straight edgeportion of said member comprising a separate part pivoted to the member,releasable means being provided on said member and said separate partfor selectively releasably retaining said separate part in outwardlyprojecting position or in inwardly folded position.

4. A protractor comprising a plate providing opposite straight lateralside edges in parallelism, a member superposed on said plate and beingpivoted thereto at a point substantially closely adjacent one end of theplate, said member having an outer straight edge portion longitudinallyoutwardlyofsaid pivot to lie free and unobstructed beyond the pivot endof said plate and laterally across the same within a predetermined rangeof various angularly adjusted positions of said member on said pivotwith respect to said plate, and said outer straight edge portion of saidmember extending'in lateral direction from said pivot toward one of saidstraight lateral side edges of said plate but not beyond said side edgein any angularly adjusted position of said plate and member and therebydefining a variable outside angle corner on the protractor for gauginginside angle corners, said member having an inner straight edge portionparallel to said outer straight edge portion thereof projecting beyondthe other said straight lateral side edge of said plate and therebyforming therewith an inside angle corner which is variablecorrespondingly to the angles of said outside angle corner of theprotractor for gauging outside angle corner, and means on said plate andmember for indicating the angular variations of said inside and outsideangle corners of the protractor, said pivot being substantiallycentrally from said lateral side edges of said plate, the edge portionsat said one end of said plate being inwardly. divergent from a point ata radius from said pivot.

WARREN B. WEYRICK.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 70,547 Graham Nov. 5, 1867511,746 Bates Jan. 2, 1894 685,372 Duncan 1- Oct. 29, 1901 1,455,708Brown May 15, 1923 2,033,626 Bozzer June 4, 1935 FOREIGN PATENTS NumberCountry Date 16,708 Great Britain Sept. 19, 1892 218,135 Great BritainJuly 3, 1924 357,925 Great Britain Oct. 1, 1931

